I'm surprised that nobody replied in almost a month!
Well, Gold Class isn't an aggressive polish/wax, so if you wanted to put another coat on a week later, you shouldn't need to worry about it. (this said 3 weeks after you would have made the decision.

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Alot of people like the look of Gold Class, so if you're happy with the look, stay with it. Just because someone else likes a different look, that doesn't mean you will. Thus so many different waxes/sealants to choose from!
Another thing to consider using is a qd. This can help to keep the car clean and extend the life of the wax. If you wanted to keep with store brands, the Meguiar's line has "Quick Detailer" (very nice sprayer-mist wise), Mothers has "Showtime" (smells like cinnamon) and another good one is Eagle One "Wipe and Shine." All can be found for under $5.00, but sometimes can be more, depending on where you shop.
With black (and new) you should go with microfiber cloths (don't look for the lowest price). They can help reduce micromarring.
Also, don't use the automatic with brushes car wash. They'll add some marring of some sort. Even if it's only minimal, it accumulates. Try to do everything carefully by hand.
Hope this can be of some help, but, as is often said, use the "search" function and you can get a lot more info.